Tech Tent 38: Ello World!

Uber: The US startup that taxi companies around the world love to hate. Co-founder Travis Kalanick talks to us on why he thinks his ride-sharing company is misunderstood, and how he will continue the firm's aggressive expansion into new countries and areas of business.

Also, why has Microsoft chosen such a low-key unveiling for its new version of Windows?

And we speak to Todd Berger, one of the creators of the new social network Ello which has created a buzz this week. Plus, Star Trek's Captain Kirk, aka William Shatner, tells us which technologies from the show he'd like to see coming our way soon.

Presented by Rory Cellan-Jones, with Leo Kelion and Dave Lee from the BBC online technology desk, and special guest, the technology journalist Kate Bevan.